Model train control actuating mechanism



Oct. 15, 1957 D. J. FOWLER 2,810,067

MODEL TRAIN CONTROL ACTUATING MECHANISM Filed Dec. 9, 1955 92 D00Iva/45a IN V EN TOR.

United States MODEL TRAIN CONTRGL ACTUATING MECHANISM This inventionrelates to model train system signaling equipment and particularly to anovel mechanism for actuating the same.

The pseudo trafiic control devices employed in miniature train systemsare made to resemble the full size real traific control device employedfor regulating train traffic on commercial railways. One of the defectsnot heretofore eliminated from the pseudo traffic control devices ofminiature railway systems is that these control devices, being solenoidoperated, move from one extreme position to the other very rapidly. Thisaction distinguishes the pseudo miniature devices from the full sizecommercial control devices in that the latter are motor operated andtheir movement from one position to the other covers a considerable timeinterval.

It is an object of the present invention to provide an inexpensiveactuating mechanism for pseudo miniature railroad control devices whichactuates the visible elements of the latter in a manner to consumepractically the same time interval for said elements to shift from oneextreme position to another as is required by the corresponding fullsize commercial control devices.

It is a further object of this invention to provide such an actuatingmechanism which is simple and inexpensive to manufacture and which willbe relatively free of maintenance troubles.

Still another object of the invention is to provide such an actuatingmechanism, the assembly of which in proper operative relation with aminiature signaling device is simple, and may therefore be performed byinexperienced labor with few tools.

Devices heretofore provided for achieving the general object of thepresent invention have failed. I discovered that this failure was aresult of their using a dash-pot for retarding the motion of a miniaturerailroad signal and that the reason for this failure is that the forcesavailable for the actuation of these miniature signals are so small thatthe dash-pots employed in said devices were inoperative to exercise asatisfactory and uniform retarding action on said miniature signals.

It is also an object of the present invention to provide an actuatingmechanism for miniature railroad signals which will include a motiondampener for said signals which will retard the motion of said signalsin a given operation of the latter substantially uniformly from thebeginning of said motion to the end thereof.

I also discovered that the lack of uniformity in the restraint providedby dash-pots used in prior miniature signal actuators resulted from thefact that each of these dash-pots necessarily embodied a stuffing boxwhich made a tight packing around the stem of the dash-pot and thefriction of this packing against the stem, if sufiicient to preventleakage of the liquid in the dash-pot, made the resistance to movementof said stem so great as to be beyond the power available for actuatingthe dash-pot in such a miniature signal actuator. I also noted that ifthe friction thus set up in the stufling box of the dashatent C) ice 2pot was reduced by loosening the same, a leakage of the fluid from thedash-pot would occur with the result that the dash-pot would soon berendered inoperative by losses from the operating liquid therein.

Another important object of the present invention is therefore theprovision of an actuating mechanism for miniature railroad signals whichwill include a motion dampener for said signals which will not require astuffing box.

The manner of accomplishing the foregoing objects as well as furtherobjects and advantages will be made manifest in the followingdescription taken in connection with the accompanying drawings in WhichFig. l is a diagrammatic vertical sectional view through the roadbed ofa miniature railway system and illustrating a semaphore mounted on topof said roadbed and a preferred embodiment of the actuating mechanism ofthe invention mounted on the bottom face of said roadbed in associationwith said semaphore for the purpose of actuating the latter. This viewshows said mechanism energized to shift said semaphore into stopposition and with said semaphore positioned as at the conclusion of itsresponse to said mechanism.

Fig. 2 is a view similar to Fig. l and illustrates said mechanismpositioned as when actuated to move said semaphore to go position, andshowing said semaphore at the conclusion of its movement to saidposition.

Fig. 3 is an enlarged sectional detailed vieW taken on line 3-3 of Fig.l and showing the manner in which a viscous liquid is employed to dampenthe action imparted by said mechanism to said semaphore.

Fig. 4 is a horizontal fragmentary sectional view taken on line 4-4 ofFig. 3.

Referring specifically to the drawings, the invention is there shown asembodied with a horizontal deck-board 10 which constitutes the roadbedof a miniature railway system. The track (not shown) of said system ismounted on top of deckboard 10 and the miniature train travels on saidtrack and is energized by electricity supplied to the rails of saidtrack. Various pseudo traffic control devices simulating actual controldevices used in commercial railway systems are mounted on the deckboard10 alongside said track, giving the appearance of reality to theoperation of miniature trains on said track. Such control devicesinclude semaphores, crossing barrier arms,

etc.

The invention comprises a control device actuating mechanism 15 which,for illustrative purposes, is shown in the drawings as secured to thebottom face of deckboard 10 by a bolt 16 which also secures to the upperface of said deckboard a semaphore control device 17.

The mechanism 15 has a frame plate 18 and an attaching flange 19 whichis bent from the upper edge thereof and apertured to receive the bolt 16and a screw 20 which cooperates with the bolt 16 to hold the mechanism15 firmly mounted on the deckboard 10. The plate 18 has a notch 24formed in an upper corner thereof, a bearing ear 25 being bent from saidplate therefrom along the horizontal edge of said notch. The bearing car25 has a bearing aperture 26 which is concentric with a cylindricalclamp 27, the latter being secured to plate 18 by a screw 28. Mounted inclamp 27 is a cylindrical tube 29 which is open at opposite ends and hasa smooth bore 30. A substantial portion of the surface of said bore iscovered by a highly viscous fluid 31. A fluid suitable for this use isknown by the trade-name Silicone, and is made by the Dow CorningCorporation, said fluid being produced in various viscosities varyingbetween 0.65 and 1,000,000 centistokes. Silicone of the Dow Corning 200series with a viscosity of 1,000,000 centistokes is preferable for usefor the fluid 31. This fluid also has the property of remaining atsubstantially uniform viscosity under widely varying conditions oftemperature and humidity. It is technically referred to inchemicalliterature as a dimethylsiloxane polymer.

Only a very thin layer of the fluid 31 need be applied to the bore 3 ofthe tube 29, the viscosity of said fluid being such that it will notflow from said tube but will remain in adhering relation therewith eventhough said tube be disposed vertically by the mounting of the mechanismand be open at both ends.

Slidable in the cylinder 29, and spaced therefrom by a thin film offluid 31, is a piston 35 having an axial bore 36 in which a piston rod37 is secured as by nuts 38 and 39. The piston rod 37, which constitutesa signal actuating member, extends slidably through the bearing opening26 and has a yoke-spool 40 slidable thereon beneath the bearing car 25.

The yoke-spool 40 has major flanges 41 and 42 and a secondary flange 43.Coiled about the rod 37 and having one end fastened to the piston 35 bythe nut 39 and the other end secured to the spool 40, by being woundabout the lower end of the latter above the flange 43, is a signalactuating coil spring 50, this spring being of a diameter which permitsit to readily fit within the bore 30 without its contacting the layer ofviscous liquid 31. In other words the outside diameter of the spring isslightly less than that of the piston 35.

Mounted on the piston rod 37 where this extends above the bearing 25 isa pair of collars 51 and 52 which are adjustably held in place on saidrod by screws 53.

Mounted on head plates 54 and 55 fixed on the plate 18 is a solenoid 56comprising coils 57 and 58. These coils are supplied with electricitythrough terminals 59, 60 and 61 whereby they may be independently andalternately energized by electrical circuits including switches (notshown) which are mounted on deckboard 10 close to said track so as to beclosed by a miniature train passing thereover. The coils 57 and 58 arein abutting coaxial relation so as to have a common bore 65 in which anarmature 66 is freely slidable. Fixed on the armature and extendingcoaxially upward therefrom is a flexible Wire link member 67, the upperend of which terminates in an eye 68.

The plate 18 also has mounted thereon a spring post 69 (Fig. 2) and alever axle bearing 70 (Fig. 4). Bear,-

ing '7 0 comprises a tube with one end 71 thereof turned,

down and threaded to receive a nut 72 after said end has been extendedthrough a suitable hole provided in the plate 18. The nut 72 istightened to draw the shoulder formed by the end portion 71 against theplate 18 and thus rigidly mount the tubular bearing 70 on said,

plate.

Journaled in the bearing 70 is an axle 75 of a lever 76. The axle 75comprises a bolt, the head 77 of which.

abuts against the end portion 71 of bearing 70 while the threaded freeend of the axle carries nuts 78 and 79 and a lock-washer 80, with saidaxle extending through a suitable aperture of the lever 76 so that theclamped between the nut 78 and washer 80 to rigidly unite the lever 76and the axle 75. A smooth washer 81 is placed on the axle 75 betweenbearing '70 and nut 78 to facilitate free rotation of said axle in saidhearing.

The lever 76 comprises a flat plate having an arm 85 bent therefromtowards the plate 18. Yoke arms 86 are formed on the arm 85 with thearms 86 extending between the flanges 41 and 42 of the spool 40 so thatrotation of the lever 76 about the axis of the bearing 70 shifts thespool 40 lengthwise on the piston rod 37.

Also fixed on the lever 76 are a short post 90, which extends inwardlytherefrom and is notched to receive and retainthereon the solenoid eye68, and a spring attaching post 91- which extends outwardly therefromand is suitably notched to receive one end ofa pre-loading coil springlatter is.

92 the opposite end of which loops around'the 4 post 69. As clearlyevident from a comparison of Figs. 1 and 2 the post 69 is so located onthe plate 18 with reference to the axis of spring 92 that the latterlies on opposite sides of the lever axle 75 when the lever 76 isdisposed in its extreme positions shown in these two views. In otherwords, the axis of the tension applied by the pre-loading spring 92 tothe lever 76 passes over dead-center each time the lever is shifted fromone of its extreme positions shown in Figs. 1 and 2 to the other of saidpositions, spring 92 thereby operating to hold the lever 76 in either ofsaid extreme positions to which it is shifted and pre-load actuatingspring 50 in either an expansive or contractile, pre-loaded condition.Spring 92 is thus seen to operate as a detent means for retaining lever76 in either of its extreme positions.

The semaphore device 17 comprises a die-cast stand ard which is hollowand has a pedestal base 101 which is suitably apertured to receive thebolt 16 in order to mount the standard 100 on the deckboard 10, with thehollow interior of the standard 100 in vertical alignment with a hole102 formed in said deckboard. Pivotally mounted on a shaft 103 whichjournals in a suitable bearing provided near the upper end of saidstandard is a semaphore arm 104. The shaft 103 has an arm 105 whichextends through an eye 106 formed in the upper end of a wire 107 whichextends downwardly through said standard andthe hole 102. The lower endof said wire 107 has an eye 108 formed thereon which is bent intohorizontal position so as to surround the piston rod 37 between thecollars 51 and 52.

Operation As, already noted, the actuating mechanism 15 is responsive tothe closing of switches (not shown) which are engaged by a miniaturetrain at various points in its travel along a track mounted on, the deckboard 10. The semaphore 17 is located near one of said switches so thatwhen the latter is closed it will energize the coil 58 of the solenoid56 so as to rock the lever 76 into the position in which this is shownin Fig. 1. This results in the semaphore arm 104 being rotated 90 fromthe position in which this is shown in Fig. 2 to the position in whichthis is shown in Fig. l. The horizontal position of the semaphore arm104 shown in Fig. 1 is its stop position in which it warns followingtrains to halt because of their proximity tothe train which closed theswitch causing the semaphore to be. shifted. to this position.

'When the leading train has advanced a. certain distance beyond thesemaphore device 17 it will engage another switch (not shown) which willenergize the coil 57 through the terminals 59. and 60 which will rockthe lever 76 from its position in Fig. l toits position in Fig. 2. Thiswill result in the semaphore arm 104 being swung 90 into its uprightposition.

It is to be noted that each movement of the lever 76' between itstwoextreme positions shown. in Figs. 1 and 2 by the energizing solenoidcoils 57 and 58 is a very rapid movement taking place in a smallfraction of. a second while the movement of the semaphore arm 104'between its two extreme positions shown in these views is a relativelyslow movement taking from two to four seconds.v A simulation is thuseffected in the opera tion of the semaphore arm 104 of the operation ofcorresponding semaphore arms in a real train signaling system where thesemaphore arms are motor-driventhrough gears andmove slowly.

The slowing down of the movements of'the semaphore arm 104 isaccomplished in the present invention by the retarding effect of theviscous liquid 31' coating the bore 30' of the cylinder 29; The movementof'the. piston 35" in the cylinder is accomplished by the exertiontherethe latter is shifted either upwardly or downwardly by the solenoid56.

For example, when the piston 35 is in upward position in the cylinder 29as shown in Fig. 3 and the coil 57 of the solenoid is energized theaction of the latter is to swing the lever 76 to the position in whichthis is shown in Fig. 2, thereby very rapidly shifting the spool 40 fromits upper position as shown in Fig. l to its lower position in which itis shown in Fig. 2. This pre-loads signal actuating spring 50 againstthe upper end of piston 35 and the passage of the pre-loading spring 92over dead-center holds the lever 76 and spool 40 as thus positionedafter the train has passed over the switch which energized the coil 57,thereby de-energizing the latter.

The pressure of signal actuating spring 50 against the piston 35, whensaid actuating spring is thus pre-loaded is insufficient to overcome theviscosity of the liquid 31 which engages and adheres to both thecylinder bore 30 and the piston 35, excepting to effect a relativelyslow movement of said piston downwardly in said bore. Thus two or threeseconds are consumed by the piston 35 in its downward travel to thepoint shown in Fig. 2 where the collar 52 rests against the guidebearing 25. In this movement the eye 108 is engaged by the collar 51 andthe wire 107 pulled downwardly so that the eye 106 on the upper end ofsaid wire, and through which the arm 105 extends, swings said armdownwardly and rotates the shaft 103 to swing semaphore arm 104 throughan arc of 90.

The collar 51 is positioned on the piston rod 37 at a level which willproduce the precisely right amount of rotation of shaft 103 to swing thesemaphore arm 104 exactly one-quarter turn upwardly as a result of theactuation of the mechanism 15 illustrated in Fig. 2. The rod 37 is ofsuch length that when it is in its upper position as shown in Fig. 1, itwill engage the deckboard which forms an upward limit stop for the rod.The collar 52 is adjustably located on the rod 37 so that when this rodis in its upper position as shown in Fig. l the eye 108 will rest on topof said collar and the wire 107 will be elevated so as to just lower thesemaphore arm 104 to the horizontal position in which this is shown inFig. 1.

The cylinder 29, piston 35 and viscous liquid 31 may be said to comprisea motion dampener 110.

While the function of the motion dampener 110 in retarding the responseof the rod 37 to the pre-loaded ctuating spring 50 is similar to thatwhich a dash-pot is ordinarily employed to perform, it performs thisfunction in an entirely different way than a dash-pot and produces asuccessful actuator for miniature signal devices, such as a miniaturetrain semaphore, where the amounts of power available for use are sosmall that a dash-pot would be wholly inoperative. The reason for thesuccess of the present invention in performing this function is that itdoes not employ any packing, such as the stufiing box of a dash-pot,which stufiing box otters a very substantial resistance to movement ofthe piston rod through it, and this resistance varies with the tightnessof the box.

The resistance of the motion dampener 110 to movement of the rod 37 isvery slight, and it is almost absolutely uniform over long periods oftime and under radical variations in temperature. No adjustments in thedampener 110 are required (nor is any possible) which can vary theresistance inter-posed thereby in the actuation of a miniature signal bythe actuating mechanism of the invention. This dampener thus entirelyovercomes the handicaps of prior miniature signal actuators whichrendered these inoperative, or at least impractical, for use for theirintended purpose.

Although this invention is disclosed as employed in actuating aminiature semaphore, it is to be understood that it may be applied withequal effectiveness for operating any other miniature device whichrequires slowing down of movement to simulate the action of theprototype.

The claims are: r

1. A mechanism for the actuation of a miniature railway system trafiiccontrol device comprising: a cylinder, a piston slidable in saidcylinder; a piston rod connected to said piston; a relatively highlyviscous liquid means disposed between said piston and said cylinder; anactuating coil spring surrounding said piston rod with one end thereofconnected to said piston; means connecting said piston rod to saidtraffic control device whereby linear movement of said rod actuates saiddevice; a solenoid; and means connected to the opposite end of saidactuating spring and operable by said solenoid to optionally stretch orcompress said actuating spring to apply a resilient force to said pistonto cause a linear shifting of said piston and rod in either directionbetween two positions of the same, the speed at which said rod shifts ineither direction in its movement between said two positions beingretarded by the viscous liquid means between said.

cylinder and said piston.

2. A combination as in claim 1 in which a lost motion means is providedbetween said rod and said means connecting said rod to said tralficcontrol device, whereby an initial portion of each linear movement ofsaid rod does not affect said device, movement of the latter beingresponsive only to the balance of said linear movement of said rod.

3. A combination as in claim 1 in which the means connecting saidsolenoid with said actuating spring comprises a lever pivotally mountedon an axis disposed at right angles to the axes of said rod and saidsolenoid, said solenoid having a core and a link member connecting saidcore to said lever; means connecting said actuating spring to said leveradjacent to the axis of said rod; a pre-loading spring connected to saidlever and held in tension so as to swing across the axis of the mountingof said lever when said solenoid is actuated to swing said lever tostretch or compress said actuating spring, said pre-loading springoperating when shifted across deadcenter by the rotation of said leverto hold said lever in the position to which the latter is shifted bysaid solenoid whereby said lever pre-loads said actuating spring in astretched or compressed condition as the case may be.

4. A combination as in claim 2 in which said means for connecting saidrod to said traffic control device comprises a wire with a loop circlingsaid rod, and a pair of collars adjustably mounted on said rod inopposite directions from said loop whereby the period of said lostmotion may be predetermined by the selection of the locations of saidcollars on said rod.

5. A mechanism for the exercise of a retarded control functioncomprising: a solenoid; a lever operatively connected to said solenoidfor optional actuation thereby in either direction between two extremepositions; a preloading spring, one end of which is connected to saidlever and the other end of which is anchored at a fixed point to causesaid spring to be under tension along a line which crosses therotational axis of said lever when the latter swings from one extremeposition to the other; a control actuating member; an actuating springconnected at one end to said member and at the other end to said leverwhereby the shifting of said lever to one of its extreme positionspre-loads said actuating spring under a contractile tension which istransmitted through said actuating spring to said actuating memberwhereas a shifting of said lever to its other extreme position preloadssaid actuating spring under an expansive tension which is likewisetransmitted to said actuating member; and a motion dampener connected tosaid actuating member to substantially uniformly retard movement of saidactuating member in response to either of said spring tensions appliedto said actuating member by said actuating spring.

6. A combination as in claim 5 in which said motion internally with ahighly viscous liquid means, and a piston which makes a loose slidingfit within said cylinder so that said liquid means forms a layerseparating said piston from said cylinder and adhering'to both, and inwhich said actuating member comprises a piston rod for said piston andin which said actuatingspring is coiled about said rod'with one endof-said spring connected to said piston and the other end of said springconnected to said lever.

7. A mechanism for'the exercise of a retarded control function whichcomprises a solenoid; an element operatively connected to said solenoidand responsive to the energizing of'the 'latter for the optionalshifting of said element to either one of two extreme positions; detentmeans forretaining said element in .wliichever of said extreme positionssaid element is shifted by said solenoid; an actuating member;anactuating spring interposed between and 'connected'at its opposite endsto said element and to said member whereby the shifting of said element20 into one of its extreme positions aforesaid pre-loads said actuatingspring under a tension which is transmitted through said actuatingspring to said actuating member tending to move said actuating member tocause the lat-' ter to exercise a'control function; and a motiondampener connected to said actuating member'to retard the response ofsaid actuating member to the tension imparted to said pre-loadedactuating spring by the shifting of said element.

8. A combination as in claim 7 in which said motion dampener comprisesmeans providing two slidably related elements said means being connectedto said actuating member to produce sliding movement between saidelements in response to the aforesaid movement of said actuating member;and viscous liquid means occupying the space between said relatedelements and thus retarding said movement of said actuating member.

References Cited in the file of this patent UNITED STATES PATENTS

